System and method for a forward link only physical layer

ABSTRACT

Systems and methods are provided for processing forward link only (FLO) signals. A device receives a FLO signal, processes a TDM pilot comprising a TDM Pilot  1 , a TDM Pilot  2 , a WIC, a LIC, a Transition Pilot Channel, and a Positioning Pilot, from the FLO signal, processes an overhead information symbol (OIS) comprising a wide-area OIS and a local-area OIS, from the FLO signal, processes an FDM pilot comprising a wide-area FDM pilot and a local-area FDM pilot, from the FLO signal; and processes data comprising wide-area data and local-area data, from the FLO signal.

CLAIM OF PRIORITY UNDER 35 U.S.C. §119

The present Application for Patent claims priority to ProvisionalApplication No. 60/703,315, entitled “FLO Air Interface” filed Jul. 27,2005, and assigned to the assignee hereof and hereby expresslyincorporated by reference herein.

REFERENCE TO CO-PENDING APPLICATIONS FOR PATENT

The present Application for Patent is related to the followingco-pending U.S. Patent Applications:

“System and Method for a Forward Link Only Protocol Suite,” applicationSer. No. 11/495,324, filed concurrently herewith, assigned to theassignee hereof, and expressly incorporated by reference herein; and“System and Method for Forward Link Only Messages,” application Ser. No.11/495,267, , filed concurrently herewith, assigned to the assigneehereof, and expressly incorporated by reference herein.

BACKGROUND

I. Field

The subject technology relates generally to communications systems andmethods, and more particularly to systems and methods for a forward linkonly wireless system.

II. Background

Forward Link Only (FLO) is a digital wireless technology that has beendeveloped by an industry-led group of wireless providers. FLO technologyuses advances in coding and interleaving to achieve high-qualityreception, both for real-time content streaming and other data services.FLO technology can provide robust mobile performance and high capacitywithout compromising power consumption. The technology also reduces thenetwork cost of delivering multimedia content by dramatically decreasingthe number of transmitters needed to be deployed. In addition, FLOtechnology-based multimedia multicasting complements wireless operators'cellular network data and voice services, delivering content to the samecellular handsets used on 3G networks.

The FLO wireless system has been designed to broadcast real time audioand video signals, apart from non-real time services to mobile users.The respective FLO transmission is carried out using tall and high powertransmitters to ensure wide coverage in a given geographical area.Further, it is common to deploy 3-4 transmitters in most markets toensure that the FLO signal reaches a significant portion of thepopulation in a given market. During the acquisition process of a FLOdata packet several determinations and computations are made todetermine such aspects as frequency offsets for the respective wirelessreceiver. Given the nature of FLO broadcasts that support multimediadata acquisitions, efficient processing of such data and associatedoverhead information is paramount. For instance, when determiningfrequency offsets or other parameters, complex processing anddeterminations are required where determinations of phase and associatedangles are employed to facilitate the FLO transmission and reception ofdata.

Wireless communication systems such as FLO are designed to work in amobile environment where the channel characteristics in terms of thenumber of channel taps with significant energy, path gains and the pathdelays are expected to vary quite significantly over a period of time.In an OFDM system, the timing synchronization block in the receiverresponds to changes in the channel profile by selecting the OFDM symbolboundary appropriately to maximize the energy captured in the FFTwindow. When such timing corrections take place, it is important thatthe channel estimation algorithm takes the timing corrections intoaccount while computing the channel estimate to be used for demodulatinga given OFDM symbol. In some implementations, the channel estimate isalso used to determine timing adjustment to the symbol boundary thatneeds to be applied to future symbols, thus resulting in a subtleinterplay between timing corrections that have already been introducedand the timing corrections that will be determined for the futuresymbols. Further, it is common for channel estimation block to processpilot observations from multiple OFDM symbols in order to result in achannel estimate that has better noise averaging and also resolveslonger channel delay spreads. When pilot observations from multiple OFDMsymbols are processed together to generate channel estimate, it isimportant that the underlying OFDM symbols are aligned with respect tothe symbol timing.

SUMMARY

The following presents a simplified summary of various embodiments inorder to provide a basic understanding of some aspects of theembodiments. This summary is not an extensive overview. It is notintended to identify key/critical elements or to delineate the scope ofthe embodiments disclosed herein. Its sole purpose is to present someconcepts in a simplified form as a prelude to the more detaileddescription that is presented later.

Systems and methods are provided for processing forward link onlywireless signals involving processing a TDM pilot, an overheadinformation symbol, an FDM pilot, and data. Processing an overheadinformation symbol (OIS) comprises a wide-area OIS and a local-area OIS,from the FLO signal, wherein the wide-area OIS conveys informationrequired to locate relevant data symbols in a wide-area data channel;

To the accomplishment of the foregoing and related ends, certainillustrative embodiments are described herein in connection with thefollowing description and the annexed drawings. These aspects areindicative of various ways in which the embodiments may be practiced,all of which are intended to be covered.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a wireless network system for forward link onlynetworks in accordance with an embodiment.

FIG. 2 is a diagram illustrating an architecture reference model inaccordance with an embodiment.

FIG. 3 is a diagram illustrating a layering architecture for the systemin accordance with an embodiment.

FIG. 4 is a diagram illustrating the Physical layer in accordance withan embodiment.

FIG. 5 is a diagram illustrating the Physical Layer Superframe Structurein accordance with an embodiment.

FIG. 6 is a diagram illustrating a protocol suite showing each of thelayers in accordance with an embodiment.

FIG. 7 is a diagram illustrating the structure of a FlowID in accordancewith an embodiment.

FIG. 8 is a diagram illustrating an example user device for a wirelesssystem.

FIG. 9 is a diagram illustrating an example base station for a wirelesssystem.

DETAILED DESCRIPTION

As used in this application, the terms “component,” “network,” “system,”and the like are intended to refer to a computer-related entity, eitherhardware, a combination of hardware and software, software, or softwarein execution. For example, a component may be, but is not limited tobeing, a process running on a processor, a processor, an object, anexecutable, a thread of execution, a program, and/or a computer. By wayof illustration, both an application running on a communications deviceand the device can be a component. One or more components may residewithin a process and/or thread of execution and a component may belocalized on one computer and/or distributed between two or morecomputers. Also, these components can execute from various computerreadable media having various data structures stored thereon. Thecomponents may communicate over local and/or remote processes such as inaccordance with a signal having one or more data packets (e.g., datafrom one component interacting with another component in a local system,distributed system, and/or across a wired or wireless network such asthe Internet).

The FLO technology was designed in an embodiment for a mobile multimediaenvironment and exhibits performance characteristics suited for use oncellular handsets. FIG. 1 illustrates a wireless network system 100 forforward link only networks in accordance with an embodiment. The system100 includes one or more transmitters 110 that communicate across awireless network 112 to one or more receivers 120. The receivers 120 caninclude substantially any type of communicating device such as a cellphone, computer, personal assistant, hand held or laptop devices, and soforth. Portions of the receiver 120 are employed to decode a symbolsubset 130 and other data such as multimedia data. The symbol subset 130is generally transmitted in an Orthogonal Frequency DivisionMultiplexing (OFDM) network that employs forward link only (FLO)protocols for multimedia data transfer. Channel estimation is generallybased on uniformly spaced pilot tones inserted in the frequency domain,and in respective OFDM symbols. The pilots are spaced 8 carriers apart,and the number of pilot carriers is set at 212.

In an embodiment, a FLO system multicasts several services. A service isan aggregation of one or more independent data components. Eachindependent data component of a service is called a flow. For example, aflow can be the video component, audio component, text or signalingcomponent of a service.

In an embodiment, services are classified into two types based on theircoverage: Wide-area services and Local-area services. A Local-areaservice is multicast for reception within a metropolitan area. Bycontrast, Wide-area services are multicast in one or more metropolitanareas.

FLO services are carried over one or more logical channels. Theselogical channels are called Multicast Logical Channels or MLCs. In anembodiment, an MLC may be divided into a maximum of three logicalsub-channels. These logical sub-channels are called streams. Each flowis carried in a single stream.

In general, FLO technology utilizes Orthogonal Frequency DivisionMultiplexing (OFDM), which is also utilized by Digital AudioBroadcasting (DAB), Terrestrial Digital Video Broadcasting (DVB-T), andTerrestrial Integrated Services Digital Broadcasting (ISDB-T).Generally, OFDM technology can achieve high spectral efficiency whileeffectively meeting mobility requirements in a large cell SFN. Also,OFDM can handle long delays from multiple transmitters with a suitablelength of cyclic prefix; a guard interval added to the front of thesymbol (which is a copy of the last portion of the data symbol) tofacilitate orthogonality and mitigate inter-carrier interference. Aslong as the length of this interval is greater than the maximum channeldelay, reflections of previous symbols are removed and the orthogonalityis preserved.

FIG. 2 is a diagram illustrating an architecture reference model inaccordance with an embodiment. The reference model consists of thefollowing functional units: The FLO device 202 and the FLO network 204.The reference model includes the air interface 206 between the FLOdevice and the FLO network. From the perspective of this reference modelthe FLO Network consists of multiple transmitters. In the FLO system,transmitters within a metropolitan area transmit identical waveforms.The term Local-area is used to denote such a group of transmitters.Transmitters in one or more metropolitan areas that multicast the sameWide-area services constitute a Wide-area. Hence, a Wide-area consistsof one or more Local-areas, with the transmitters in the differentLocal-areas multicasting different Local-area services. As a result, thetransmit waveform is not identical for all Wide-area transmitters.Finally, transmitters in different Wide-areas also transmit differentwaveforms, since they multicast different Wide-area and Local-areaservices.

The air interface is layered, with the interface defined for each layer.FIG. 3 is a diagram illustrating a layering architecture 300 for the FLOSystem in accordance with an embodiment. The layers are:

-   -   Upper Layers 302: The “upper” protocol layers provide multiple        functions including compression of multimedia content,        controlling access to the multimedia content and formatting of        Control information.    -   Control Layer 304: This layer is used by the network to        disseminate information to facilitate the device operation in        the FLO system. The device uses the Control layer to maintain        synchronization of its Control information with that in the        network.    -   Stream Layer 306: The Stream layer provides for binding of upper        layer flows to streams on an MLC-by-MLC basis. The Stream layer        is at the same level as the Control layer in the air interface        layering architecture.    -   MAC Layer 308: This layer does multiplexing of packets belonging        to different media streams associated with MLCs. The MAC (Medium        Access Control) layer defines the procedures used to receive and        transmit over the Physical layer.    -   Physical Layer 310: The Physical layer provides the channel        structure, frequency, power output, modulation and encoding        specification for the Forward Link.

The Physical layer defines the FLO Physical layer channels andhierarchies shown in FIG. 4 in accordance with an embodiment. The FLOPhysical Layer 400 Channel 402 comprises a TDM Pilot 406, OIS 408, FDMPilot 410, and Data 412. The TDM Pilot Channel comprises the componentchannels TDM Pilot 1 414, TDM Pilot 2 416, Transition Pilot Channel 418,WIC 420, LIC 422, and Positioning Pilot/Reserved Symbols 424. The OIS408 comprises a Wide-area OIS 426 and a Local-area OIS 428. The FDMPilot 410 comprises a Wide-area FDM Pilot 430 and a Local-area FDM Pilot432. Data 412 comprises Wide-area Data 434 and Local-areaData 436.

The transmitted signal in the FLO system is organized into superframes.In an embodiment, each superframe has duration of Is. In an embodimenteach superframe comprises 1200 OFDM symbols.

The term Wide-area refers to a group of transmitters radiating identicalwaveform and with a footprint covering one or more metropolitan areas.The term Local-area refers to group of transmitters radiating identicalwaveforms with a footprint that is less than that for a Wide-area.

FIG. 5 is a diagram illustrating the FLO Physical Layer SuperframeStructure 500 in accordance with an embodiment. It shows the generalrelationship (not to scale) between the various Physical layer channels.

In an embodiment, a superframe is equal to 1200 OFDM symbols with a onesecond time duration. The FLO physical layer uses a 4K mode (yielding atransform size of 4096 sub-carriers), providing superior mobileperformance compared to an 8K mode, while retaining a sufficiently longguard interval that is useful in fairly large SFN cells. Rapid channelacquisition can be achieved through an optimized pilot and interleaverstructure design. The interleaving schemes incorporated in the FLO airinterface facilitate time diversity. The pilot structure and interleaverdesigns optimize channel utilization without annoying the user with longacquisition times.

In an embodiment, each superframe consists of 200 OFDM symbols per MHzof allocated bandwidth (1200 symbols for 6 MHz), and each symbolcontains seven interlaces of active sub-carriers. Each interlace isuniformly distributed in frequency, so that it achieves the fullfrequency diversity within the available bandwidth. These interlaces areassigned to logical channels that vary in terms of duration and numberof actual interlaces used. This provides flexibility in the timediversity achieved by any given data source. Lower data rate channelscan be assigned fewer interlaces to improve time diversity, while higherdata rate channels utilize more interlaces to minimize the radio'son-time and reduce power consumption.

The acquisition time for both low and high data rate channels isgenerally the same. Thus, frequency and time diversity can be maintainedwithout compromising acquisition time. Most often, FLO logical channelsare used to carry real-time (live streaming) content at variable ratesto obtain statistical multiplexing gains possible with variable ratecodecs (Compressor and Decompressor in one). Each logical channel canhave different coding rates and modulation to support variousreliability and quality of service requirements for differentapplications. The FLO multiplexing scheme enables device receivers todemodulate the content of the single logical channel it is interested into minimize power consumption. Mobile devices can demodulate multiplelogical channels concurrently to enable video and associated audio to besent on different channels.

Error correction and coding techniques can also be employed. Generally,FLO incorporates a turbo inner code and a Reed Solomon (RS) outer code.Typically, the turbo code packet contains a Cyclic Redundancy Check(CRC). The RS code need not be calculated for data that is correctlyreceived, which, under favorable signal conditions, results inadditional power savings. Another aspect is that the FLO air interfaceis designed to support frequency bandwidths of 5, 6, 7, and 8 MHz. Ahighly desirable service offering can be achieved with a single RadioFrequency channel.

Four of the six TDM Pilot channels namely TDM Pilot 1 502, Wide-areaIdentification Channel (WIC) 504, Local-area Identification Channel(LIC) 506 and TDM Pilot 2 508 occur consecutively during the first fourOFDM symbols in the figure. The FDM Pilot channel is frequency divisionmultiplexed with the Overhead Information Symbols (OIS) Channels andData Channels. The Transition Pilot Channel (TPC) 510 is time divisionmultiplexed with the OIS and the Data Channels over a superframe. ThePositioning Pilot Channel (PPC) 518 or 2, 6, 10, or 14 Reserved OFDMsymbols appear at the end of the superframe. In order to support thetransmission of Wide-area and Local-area services:

-   -   The OIS Channel is divided into the Wide-area OIS Channel and        the Local-area OIS Channel, which are time-division multiplexed        within the OIS Channel.

The FDM Pilot Channel 512 is divided into the Wide-area FDM PilotChannel 514 and the Local-area FDM Pilot Channel 516, which aretime-division multiplexed within the FDM Pilot Channel.

The Data Channel is divided into the Wide-area Data Channel and theLocal-area Data Channel, which are time-division multiplexed within theData Channel.

Wide-area services that are multicast in a specific Wide-area aretransmitted in the Wide-area Data Channel, while the Local-area servicesthat are multicast in a specific Local-area are transmitted in theLocal-area Data Channel.

The generic term “entity” is used to refer to either a FLO device or aFLO network. An embodiment includes the following types of interfaces:

-   -   Headers and Messages are used for communication between a        protocol executing in one entity and the same protocol executing        in another entity.    -   Commands are used by a protocol to obtain a service from another        protocol within the same FLO network or device.    -   Indications are used by a lower layer protocol to convey        information regarding the occurrence of an event. Any higher        layer protocol can register to receive these indications. A same        layer protocol can also register to receive an indication but        only in one direction.    -   Public Data is used to share information in a controlled way        between protocols. Public data is shared between protocols in        the same layer, as well as between protocols in different        layers.

Indications are always written in the past tense since they announceevents that have happened. Headers and messages are binding on allimplementations. Indications and public data are used as a device for aclear and precise specification. FLO devices and FLO networks can becompliant while choosing a different implementation that exhibitsidentical behavior.

FIG. 6 illustrates a protocol suite 600 showing each of the layers inaccordance with an embodiment. Control information 602 is shown to betransferred from the Upper Layer Protocol/Application Protocol 604 to aControl Layer 606. The Control Layer includes a Control Protocol 608.The Upper Layer Protocol/Application Protocol 604 interfaces with theStream Layer 610. The Stream Layer includes a Stream Protocol 612. TheControl Layer 606 interfaces with the MAC Layer 614 and the Stream Layer610 interfaces with the MAC Layer 614.

The MAC Layer 614 includes a Control Channel 616, an OIS Channel 618,and a Data Channel 620. The Control Channel 616, OIS Channel 618, andData Channel 620 use a MAC Protocol. The MAC Layer 614 interfaces withthe FLO Physical Layer 622.

The service offered by the FLO network consists of multicasting dataflows (referred to simply as flows) provided by the upper layers. Therole of the Control layer is to provide the device with the informationneeded to receive particular flow(s). In an embodiment, each flow isaddressed by a unique, 20-bit identifier called a FlowID 700. The FlowIDcomprises two parts: FlowID_bits_4_thru_19 702 and FlowID_bits_0_thru_3704. The structure of the FlowID in accordance with an embodiment isshown in FIG. 7.

The flows are carried over logical channels. These logical channels arecalled Multicast Logical Channels or MLCs.

The Control layer of the network disseminates information (referred toas control information) needed by the device to operate in the FLOsystem. The Control layer of the device receives this information andmaintains synchronization of its control information with that in thenetwork. The Control layer provides the latest information to otherprotocol entities. The Control layer maintains three categories ofinformation:

-   -   Flow Description Information: This includes the mapping of flows        to MLCs and flow configuration parameters.    -   Radio Frequency Channel Information: This includes the Radio        Frequency Channels in use in the FLO network.    -   Neighbor List Information: This includes the list of neighboring        Wide-areas and Local- areas.

The Control layer maintains and disseminates the information in each ofthe above categories as two logically separate classes, namely, Bin 0and Bin 1. This separation allows the network to localize updates to thecontrol information to a particular bin. This allows the FLO devices toprocess and utilize the information in one bin independent of the other.The Control layer functions are implemented by the Control protocol.

The Control protocol shall set the Control protocol packet header asshown in Table 1.

TABLE 1 Field Length (bits) Fill 0 or 8 MessageTypeID 8 Bin ID 1CPPNumber 8 TotalCPPCount 8 NumPadBytes 7Fill

Filler field for Control Channel MAC protocol header. This field shallbe present for the first CPP in a Control protocol capsule and shall beset to zero. Otherwise, this field shall be omitted. In an embodiment,Control Channel MAC protocol overwrites this field with the ControlChannel MAC Layer capsule Header

Message Type ID

The message type identifier. It shall be set based on the type ofinformation this message carries. The valid values are listed in Table2.

TABLE 2 Value Meaning 0x00 Flow Description message 0x01 RF ChannelDescription message 0x02 Neighbor List Description message 0x03 Fillermessage 0xEF-0xFF ReservedBin ID

This corresponds to one of the two logical Control protocol Bins towhich the message carried in the CPP payload is assigned by the network.The network shall set this field to the bin identifier (0 or 1) for thecontent carried in the CPP. If the MessageTypeID field is 0x03 (Fillermessage), this field may be assigned any value and is ignored by thedevice.

CPP Number

A unique number assigned to the CPP associated with the Control protocolinformation identified by the MessageTypelD for this Bin. The networkshall set its value ranging from 0 through TotalCPPCount−1.

Total CPP Count

The total number of CPPs that are associated with the Control protocolinformation identified by the MessageTypelD for this Bin. Network shallset this field to the total number of CPPs carrying the messages ofMessageTypelD.

Num Pad Bytes

The number of padding bytes included in this CPP. The network shall setthis field to the number of PadBytes.

The Flow Description Message is shown in Table 3.

TABLE 3 Field Length (bits) CPPHeader 32 or 40 FlowBlobLength 8FlowCount 7 Reserved0 1

FlowCount occurrences of the remaining fields are shown in Table 4.

TABLE 4 FlowID_bits_4_thru_19_SameAsBefore 1 FlowID_bits_4_thru_19 0 or16 FlowID_bits_0_thru_3 4 RFChannelID 8 MLCIDSameAsBefore 1 MLC_ID 0 or8 TransmitMode 0 or 4 OuterCodeRate 0 or 4 FlowBlob FlowBlobLengthStreamID 2 StreamResidualErrorProcessing 2 StreamUsesBothComponents 1Reserved1 Variable (0-7)Flow Blob Length

Length of the FlowBlob (flow information block) field. The network shallset this field to the size of the FlowBlob field included in thismessage in integer number of bits.

Flow Count

The number of flows carried in the CPP. The network shall set this fieldto number of flows that follow this field in the Flow Descriptionmessage CPP.

Reserved 0

This field shall be set to 0.

Flow ID Bits 4 thru 19 Same as Before

Flag to indicate if the FlowID_bits_4_thru_19 field for this flow is thesame as the previous flow. The network shall set this field to ‘0’ forthe first flow in the Flow Description message CPP. Otherwise, if a flowdescribed in a CPP has the same FlowID_bits_4_thru_19 as the previousflow, this field shall be set to ‘1’.

FlowID Bits 4 thru 19

This field contains the upper-16 bits (bits 4 through 19) of theidentifier (FlowID) for the flow. If FlowID_bits_4_thru_19_SameAsBeforefield is set to ‘1’, the network shall omit this field. Otherwise, thisfield shall be set to the upper 16-bits of the flow ID.

FlowID Bits 0 thru 3

The network shall set this field to the lower 4-bits of the FlowID.

RF Channel ID

Identifier for the RF Channel carrying the flow. The details ofRFChannelID are carried in RF Channel Description message.

MLC ID Same as Before

Flag to indicate if MLCID for this flow is same as the previous flow.The network shall set this field to ‘0’ for the first flow in the FlowDescription message CPP. Otherwise, if this flow has the same MLC ID asthe previous flow, this field shall be set to ‘1’.

MLC ID

If MLCIDSameAsBefore field is set to ‘1’, the network shall omit thisfield. Otherwise, this field shall contain a unique identifier of theMLC.

Transmit Mode

Transmit mode used by the MLC carrying this flow. If MLCIDSameAsBeforefield is set to ‘1’, the network shall omit this field, otherwise, thenetwork shall set this field to the Physical layer mode used to transmitthe MLC.

Outer Code Rate

Outer code rate for the MLC carrying this flow. If MLCIDSameAsBeforefield is set to ‘1’, the network shall omit this field, otherwise, thenetwork shall set this field to the outer code rate applied to the MLC.Values for the OuterCodeRate field are listed in Table 5.

TABLE 5 Value Meaning ‘0000’ None ‘0001’ Reed-Solomon encoding rate ⅞‘0010’ Reed-Solomon encoding rate ¾ ‘0011’ Reed-Solomon encoding rate ½All other values are reserved.Flow Blob

This field carries the flow information used by the upper layers. Thenetwork shall set this field as per the requirements of upper layers.

Stream ID

This 2-bit field is the stream identifier. The network shall set theStrea,mID field to the values specified in Table 6.

TABLE 6 Value Meaning ‘00’ Stream 0 ‘01’ Stream 1 ‘10’ Stream 2 Allother values are reserved.Stream Residual Error Processing

This field specifies the Stream layer residual error processing at thedevice. The network shall set this field as per the values listed inTable 7.

TABLE 7 Value Meaning ‘00’ None ‘01’ Drop All other values are reserved.Stream Uses Both Components

This field specifies if stream contains both the enhancement and basecomponents or just the base component. The network shall set this fieldto ‘0’ if stream contains only the base component. The network shall setthis field to ‘1’ if stream contains both the base and enhancementcomponents. If the MLC that this stream belongs to is using anon-layered transmit mode, then the network may set this field to anyvalue and this field is ignored by the device.

Reserved

This variable length field is added to make the Flow Description messageoctet aligned. This field shall be set to 0.

The RF Channel Description message carries the description of the RFCarriers used for carrying FLO Services. The message shall have formatshown in Table 8.

TABLE 8 Field Length (bits) CPPHeader 32 or 40 LOICount 8

Table 9 shows the LOICount occurrences of the following LOI record.

TABLE 9 LOI_ID 16 RFChannelCount 4

Table 10 shows the RFChannelCount occurrences of the following threefields.

TABLE 10 RFChannelID 8 Frequency 13 ChannelPlan 3CPP Header

The CPP header.

LOI Count

The number Local Operational Infrastructure records included in thismessage. The network shall set this field to the number of LOI Recordsincluded in the message.

LOI ID

This field contains the ID of the Local-area infrastructure identifierassociated with this LOI Record. The network shall set this field to theidentifier assigned to the Local-area infrastructure.

RF Channel Count

The network shall set this field to number of RF Channels that followthis field in the RF Channel Description message CPP.

RF Channel ID

The network shall set this field to the numerical identifier associatedwith the combination of Frequency and ChannelPlan field values includedin this record.

Frequency

The network shall set this field to the frequency offset from 470 MHz(start of the FCC Broadcast TV allocation for channels 14-69) to thecarrier center frequency in units of 50 KHz. This is calculated by theequation below:

${{Frequency} = \frac{\left( {C - 470} \right)}{0.05}},$where C is the carrier center frequency in MHz.Channel Plan

The network shall set this field to the channel plan (or ChannelBandwidth) used by the transmitter. The values for this field are listedin Table 11.

TABLE 11 Value Meaning ‘000’ 5 MHz channel ‘001’ 6 MHz channel ‘010’ 7MHz channel ‘011’ 8 MHz channel All other values are reservedReserved

This field is added to make the RF Channel Description message octetaligned. Network shall set the bits in this field to ‘0’.

The Neighbor List Description message carries the infrastructureparameters of the neighboring LOIs for a given LOI. The infrastructureparameters included are frequency, Wide-area Differentiators (WID) andcorresponding Local-Area Differentiators (LID). The message shall havethe format shown in Table 12.

TABLE 12 Field Length (bits) CPPHeader 32 or 40 LOICount 8

Table 13 shows the LOICount occurrences of the following LOI record.

TABLE 13 LOI_ID 16 FrequencyCount 4

Table 14 shows the FrequencyCount occurrences of the following FrequencyRecord

TABLE 14 Frequency 13 ChannelPlan 3 WIDCount 4

Table 15 shows the WIDCount occurrences of the following WID Record.

TABLE 15 WID 4 LIDCount 4

Table 16 shows the LIDCount occurrences of the following field

TABLE 16 LID 4The CPP Header

The CPP header.

LOI Count

The number of Local Operational Infrastructure records included in thismessage. The network shall set this field to the number of LOI Recordsincluded in the message.

LOI ID

This field contains the ID of the Local-area infrastructure identifierassociated with this LOI Record. The network shall set this field to theidentifier assigned to the Local-area infrastructure.

Frequency Count

The number of frequencies included in the LOI record. The network shallset this field to the number of Frequency records included in the LOIrecord.

Frequency

This field contains the frequency offset from 470 MHz (start of the FCCBroadcast TV allocations for channels 14-69) to the center frequency inunits of 50 kHz.

Channel Plan

This field contains the channel plan used for Local-area transmissions.

WID Count

The network shall set this field to number of WID records following thisfield.

WID

The network shall set this field to the Wide-Area Differentiatorassociated with this Wide-area.

LID Count

The network shall set this field to number of LID records following thisfield.

LID

The network shall set this field to the Local-Area Differentiatorassociated with this Local-area.

Reserved

This is a variable length field added to make the Neighbor ListDescription message octet aligned. Network shall set the bits in thisfield to ‘0’.

Table 17 shows the Filler message. The Filler message is used to fillthe unused portion of the Control protocol capsule payload after all theControl protocol messages carrying Control information have beenincluded. The Filler message does not belong to any bin. Therefore theBinID field in the CPP header of this message is included but not used.In an embodiment, the network sets all the FillerOctets bits in thisfield to ‘0’.

TABLE 17 Field Length (bits) CPPHeader 32 or 40 FillerOctets 944

The control protocol in the network shall add sufficient padding octetsto fill any unoccupied portion of the CPP. The format of PadByte isshown in Table 18.

TABLE 18 Field Value PadByte 0x00

The Stream layer resides between the MAC layer and the Upper/Applicationlayer in the FLO protocol stack as shown in FIG. 6. Data from the Upperlayer is carried in one or more flows. The Stream layer provides accessto the FLO Air Interface protocol stack for the flows to and from theUpper layer. A flow can consist of one component (referred to as thebase component) or two components (referred to as base and enhancementcomponents). When a flow has two components, the enhancement componentis tightly coupled with the base component. For example, both componentsare addressed using the same flow ID, are delivered to the same Upperlayer entity in the device and receive the same delay and errortreatment in the Stream layer.

In accordance with an embodiment, a primary function of the Stream layeris to multiplex/demultiplex up to three flows to/from a single MLC.

The Stream protocol provides the functionality of the Stream layer. Itmultiplexes Upper layer flows into a single MLC. These Upper layer flowsare transported as “streams” in an MLC. Up to three streams (referred toas stream 0, 1 and 2) are multiplexed into one MLC. Stream 0 is alwayspresent in an MLC if there is flow data to be sent for stream 1 and/orstream 2. In other words, if there is no flow data to be sent for any ofthe streams, stream 0 is not sent.

An Upper layer flow can consist of a base component and an enhancementcomponent. If both components are present, both components are carriedby the same stream. Stream 0 only carries a base component even when theassociated MLC is configured for a layered transmit mode. The other twostreams (streams 1 and 2) can carry both base and enhancementcomponents. When a stream carries an enhancement component, the Upperlayer for that flow is required to exactly match the sizes of the baseand enhancement components.

The Stream protocol supports two interface modes:

-   -   Octet flow mode in which the Stream protocol in the network        receives a stream of octets from the Upper layer and the peer        protocol in the device delivers a stream of octets.

Transparent or Block flow mode in which the Stream protocol in thenetwork receives a stream of fixed sized octet blocks and the peerprotocol in the device delivers these fixed sized octet blocks to theUpper layer.

The Stream protocol provides the TransparentModeFlag attribute to selectthe interface mode for each Upper layer flow. When this attribute is setto ‘1’, the Stream protocol receives a stream of fixed, 122 octetblocks, each of which is carried by a separate Physical layer packet.This allows the Upper layer visibility to packet boundaries at the lowerFLO protocol layers. This Transparent or Block flow mode (also referredto as the block-oriented mode) is only supported for streams 1 and 2.

If the TransparentModeFlag attribute is set to ‘0’ for a flow, theStream protocol processes the data from the Upper layer flow as a streamof octets. This interface is appropriate if the Upper layer is notconcerned with the formation of lower layer packets. Stream 0 alwaysuses this Octet flow mode (also referred to as the octet-oriented mode).Stream 1 and 2 use either of the two modes, the Block flow mode or theOctet flow mode.

The Stream protocol provides an interface to specify Stream layerresidual error processing for an Upper layer flow using theResidualErrorProcessing attribute. This selection applies to both thebase component and the enhancement component (when present) of a flow.Choices include:

None—specifies that the flow carried by the stream is to be delivered tothe Upper layer entity with no additional processing. Octets of the flowreceived in packets containing errors are delivered to the Upper layerentity.

Drop—specifies that the octets of the flow received in packetscontaining errors are to be discarded.

The Stream protocol provides an interface to specify delay constraintsfor an Upper layer flow. The delay constraint is specified in terms ofthree attributes, namely DelayConstraintType, DelayConstraintValue andStreamElasticity:

-   -   DelayConstraintType specifies the delay constraint type for a        flow. This selection applies to both the base component and        enhancement component (when present) of a flow. Choices include:        -   RealTime—specifies that the flow be delayed by a constant            value.        -   MaxDelay—specifies that the flow have a maximum delay            constraint.        -   None—specifies that the flow be sent only when extra MLC            bandwidth is available.    -   DelayConstraintValue specifies the value of the delay constraint        for an Upper layer flow when DelayConstraintType is RealTime or        MaxDelay.    -   StreamElasticity specifies how to handle the flow when the delay        constraints cannot be met. This selection applies to both the        base and enhancement (when present) components of a flow.        Choices include:        -   Elastic—specifies that the source reduces the data rate upon            request.        -   Drop—specifies that flow octets can be dropped.        -   Fragment—specifies that all or part of the octets can be            delayed.

This document assumes that there is one instance of this protocol in thenetwork for each active Data Channel MLC. In the device there is oneinstance of this protocol for each MLC that the device is decoding.

This protocol operates in one of two states:

-   -   Inactive State: In this state the protocol waits for an Activate        command.    -   Active State: In this state the protocol in the network        packetizes up to three flows, multiplexes these packets for        transmission in the associated MLC and sends them to the MAC        layer. The protocol in the device receives Stream layer packets        from the MAC layer, handles residual transmission errors and        delivers the resulting octet or octet block flows to the Upper        layer.

The Stream layer provides the following functions:

-   -   Provides an interface to bind Upper layer flows to streams in an        MLC. Each MLC can support three independent data streams.    -   Multiplexes up to three flows from the Upper layer into one MLC.    -   Accommodates delay constraints of an Upper layer flow.    -   Provides for residual error handling for an Upper layer flow.    -   Provides for independent handling of base and enhancement        components of an Upper layer flow.

The MAC layer defines the operation of Wide-area and Local-area OISChannels, Wide-area and Local-area Control Channels and Data Channels.The MAC layer also multiplexes MLCs for transmission at the FLO networkand de-multiplexes them at the FLO device. The MAC layer includes thefollowing three protocols:

-   -   OIS Channel MAC Protocol: This protocol contains the rules        governing how the FLO network builds the messages transmitted in        the OIS Channels and how the FLO device receives and processes        these messages.    -   Data Channel MAC Protocol: This protocol contains the rules        governing how the FLO network builds the MAC layer packets for        transmission of service carrying data on the Wide-area and        Local-area Data Channels and how the FLO device receives and        processes these packets.    -   Control Channel MAC Protocol: This protocol contains the rules        governing how the FLO network builds the MAC layer packets for        transmission of FLO Control information on the Wide-area and        Local-area Control Channels and how the FLO device receives and        processes these packets.

The Data Channel and Control Channel are defined at the MAC layer. Atthe Physical layer both of these channel types are carried on the sameData Channel.

The content of an MLC for one superframe is encapsulated in an entityreferred to as MAC protocol capsule. MAC protocol capsule is carried inMAC layer packets. One MAC layer packet is 122 octets in size and formsthe payload of one Physical layer packet (PLP).

The transmission unit of the Physical layer is a Physical layer packet.A Physical layer packet has a length of 1000 bits. A Physical layerpacket carries one MAC layer packet.

The FLO Physical layer is comprised of the following sub-channels:

-   -   The TDM Pilot Channel.    -   The Wide-area OIS Channel.    -   The Local-area OIS Channel.    -   The Wide-area FDM Pilot Channel.    -   The Local-area FDM Pilot Channel.    -   The Wide-area Data Channel.    -   The Local-area Data Channel.

The TDM Pilot Channel comprises the component channels TDM Pilot 1, TDMPilot 2, Transition Pilot Channel, WIC, LIC, and PositioningPilot/Reserved Symbols.

The TDM Pilot 1 Channel shall span one OFDM symbol. It shall betransmitted at the OFDM symbol index 0 in the superframe. It signals thestart of a new superfame. It may be used by the FLO device fordetermining the coarse OFDM symbol timing, the superframe boundary andthe carrier frequency offset.

The Wide-area Identification Channel (WIC) shall span one OFDM symbol.It shall be transmitted at OFDM symbol index 1 in a superframe. Itfollows the TDM Pilot 1 OFDM symbol. This is an overhead channel that isused for conveying the Wide-area Differentiator information to FLOreceivers. All transmit waveforms within a Wide-area (IncludingLocal-area channels but excluding the TDM Pilot 1 Channel and the PPC)are scrambled using the 4-bit Wide-area Differentiator corresponding tothat area. For the WIC OFDM symbol in a superframe only 1 slot shall beallocated. The allocated slot shall use as input a 1000-bit fixedpattern, with each bit set to zero.

The Local-area Identification Channel (LIC) shall span one OFDM symbol.It is transmitted at OFDM symbol index 2 in a superframe. It follows theWIC channel OFDM symbol. This is an overhead channel that is used forconveying the Local-area Differentiator information to FLO receivers.All Local-area transmit waveforms are scrambled using a 4-bit Local-areaDifferentiator, in conjunction with the Wide-area Differentiator,corresponding to that area.

For the LIC OFDM symbol in a superframe only a single slot shall beallocated. The allocated slot shall use a 1000-bit fixed pattern asinput. These bits shall be set to zero.

The TDM Pilot 2 Channel shall span one OFDM symbol. It shall betransmitted at OFDM symbol index 3 in a superframe. It follows the LICOFDM symbol. It may be used for fine OFDM symbol timing corrections inthe FLO receivers.

For the TDM Pilot 2 OFDM symbol in each superframe only 4 slots shall beallocated. Each allocated slot shall use as input a 1000-bit fixedpattern, with each bit set to zero.

The Transition Pilot Channel consists of 2 sub-channels: the Wide-areaTransition Pilot Channel (WTPC) and the Local-area Transition PilotChannel (LTPC). The TPC flanking the Wide-area OIS and the Wide-areaData Channel is called the WTPC. The TPC flanking the Local-area OIS andthe Local-area Data Channel is called the LTPC. The WTPC spans 1 OFDMsymbol on either side of every Wide-area channel transmission with theexception of WIC (the Wide-area Data and the Wide-area OIS Channel) in asuperframe. The LTPC spans 1 OFDM symbol on either side of everyLocal-area Channel transmission with the exception of LIC (theLocal-area Data and the Local-area OIS Channel). The purpose of the TPCOFDM symbol is two-fold: to allow channel estimation at the boundarybetween the Local-area and the Wide-area channels and to facilitatetiming synchronization for the first Wide-area (or Local-area) MLC ineach frame. The TPC spans 20 OFDM symbols in a superframe, which areequally divided between the WTPC and the LTPC.

In an embodiment, there are nine instances where the LTPC and the WTPCtransmissions occur right next to each other and two instances whereonly one of these channels is transmitted. Only the WTPC is transmittedafter the TDM Pilot 2 Channel, and only the LTPC is transmitted prior tothe Positioning Pilot Channel (PPC)/Reserved OFDM symbols.

Let:

-   -   P be the number of OFDM symbols in the PPC/Reserved OFDM        symbols.    -   W be the number of OFDM symbols associated with the Wide-area        Data Channel in a frame.    -   L be the number of OFDM symbols associated with the Local-area        Data Channel in a frame.    -   F be the number of OFDM symbols in a frame.

The values of P shall be 2, 6, 10 or 14. The number of Data Channel OFDMsymbols in a frame shall be F-4. The exact locations of the TPC OFDMsymbols in a superframe shall be as specified in Table 19.

TABLE 19 TPC Location Indices in a Superframe Transition Index for theIndex for the Pilot WTPC OFDM LTPC OFDM Channel Symbol Symbol TDM Pilot2 4 — Channel → Wide-area OIS Channel Wide-area OIS 10 11 Channel →Local- area OIS Channel Local-area OIS 18 17 Channel → Wide-area DataChannel Wide-area Data 19 + W + F × i, 20 + W + F × i, Channel →Local-area {i = 0, 1, 2, 3} {i = 0, 1, 2, 3} Data Channel Local-areaData 18 + F × i, 18 + F × i, Channel → Wide- {i = 1, 2, 3} {i = 1, 2, 3}area Data Channel Local-area Data — 1199-P Channel → PPC/ReservedSymbols

All slots in the TPC OFDM symbols use as input a 1000-bit fixed pattern,with each bit set to zero.

In an embodiment, the FLO device may use a Positioning Pilot Channel(PPC) either autonomously or in conjunction with the GPS signal todetermine its geographical location.

The Wide-area OIS channel is used to convey overhead information aboutthe active MLC's associated with the Wide-area Data Channel, such astheir scheduled transmission times and slot allocations, in the currentsuperframe. In an embodiment, the Wide-area OIS Channel spans five OFDMsymbol intervals in each superframe.

The Local-area OIS Channel is used to convey overhead information aboutthe active MLCs associated with the Local-area Data Channel, such astheir scheduled transmission times and slot allocations, in the currentsuperframe. In an embodiment, the Local-area OIS Channel spans five OFDMsymbol intervals in each superframe.

The Wide-area FDM Pilot Channel is transmitted in conjunction with theWide-area Data Channel or the Wide-area OIS Channel. The Wide-area FDMPilot Channel carries a fixed bit pattern that may be used for Wide-areaChannel estimation and other functions by the FLO device.

For the Wide-area FDM Pilot Channel a single slot shall be allocatedduring every OFDM symbol that carries either the Wide-area Data Channelor the Wide-area OIS Channel. The allocated slot shall use a 1000-bitfixed pattern as input. These bits shall be set to zero.

The Local-area FDM Pilot Channel is transmitted in conjunction with theLocal-area Data Channel or the Local-area OIS Channel. The Local-areaFDM Pilot Channel carries a fixed bit pattern that may be used forLocal-area channel estimation and other functions by the FLO device.

For the Local-area FDM Pilot Channel a single slot shall be allocatedduring every OFDM symbol that carries either the Local-area Data Channelor the Local-area OIS Channel. The allocated slot shall use a 1000-bitfixed pattern as input. These bits shall be set to zero.

The Wide-area Data Channel is used to carry Physical layer packets meantfor Wide-area multicast. The Physical layer packets for the Wide-areaData Channel can be associated with any one of the active MLCstransmitted in the Wide-area.

For regular modulation (QPSK and 16-QAM), the Physical layer packet isturbo-encoded and bit interleaved before being stored in the Data slotbuffer(s). For layered modulation, the base component Physical layerpacket and the enhancement component Physical layer packet areturbo-encoded and bit interleaved independently before being multiplexedinto the Data slot buffer(s).

The Local-area Data Channel is used to carry Physical layer packetsmeant for Local-area multicast. The Physical layer packets for theLocal-area Data Channel can be associated with any one of the activeMLCs transmitted in the Local-area.

For regular modulation (QPSK and 16-QAM), the physical layer packet isturbo-encoded and bit interleaved before being stored in the Data slotbuffer(s). For layered modulation, the base component Physical layerpacket and the enhancement component Physical layer packet areturbo-encoded and bit interleaved independently before being multiplexedinto the Data slot buffer(s).

FIG. 8 is an illustration of a user device 800 that is employed in awireless communication environment, in accordance with one or moreaspects set forth herein. User device 800 comprises a receiver 802 thatreceives a signal from, for instance, a receive antenna (not shown), andperforms typical actions thereon (e.g., filters, amplifies, downconverts, etc.) the received signal and digitizes the conditioned signalto obtain samples. Receiver 802 can be a non-linear receiver. Ademodulator 804 can demodulate and provide received pilot symbols to aprocessor 806 for channel estimation. A FLO channel component 810 isprovided to process FLO signals as previously described. This caninclude digital stream processing and/or positioning locationcalculations among other processes. Processor 806 can be a processordedicated to analyzing information received by receiver 802 and/orgenerating information for transmission by a transmitter 816, aprocessor that controls one or more components of user device 800,and/or a processor that both analyzes information received by receiver802, generates information for transmission by transmitter 816, andcontrols one or more components of user device 800.

User device 800 can additionally comprise memory 808 that is operativelycoupled to processor 806 and that stores information related to wirelessnetwork data processing. It will be appreciated that the data store(e.g., memories) components described herein can be either volatilememory or nonvolatile memory, or can include both volatile andnonvolatile memory. By way of illustration, and not limitation,nonvolatile memory can include read only memory (ROM), programmable ROM(PROM), electrically programmable ROM (EPROM), electrically erasable ROM(EEPROM), or flash memory. Volatile memory can include random accessmemory (RAM), which acts as external cache memory. By way ofillustration and not limitation, RAM is available in many forms such assynchronous RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM),double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), SynchlinkDRAM (SLDRAM), and direct Rambus RAM (DRRAM). The memory 808 of thesubject systems and methods is intended to comprise, without beinglimited to, these and any other suitable types of memory. User device800 further comprises a background monitor 814 for processing FLO data,a symbol modulator 814 and a transmitter 816 that transmits themodulated signal.

FIG. 9 is an illustrates an example system 900 that comprises a basestation 902 with a receiver 910 that receives signal(s) from one or moreuser devices 904 through a plurality of receive antennas 906, and atransmitter 924 that transmits to the one or more user devices 904through a transmit antenna 908. Receiver 910 can receive informationfrom receive antennas 906 and is operatively associated with ademodulator 912 that demodulates received information. Demodulatedsymbols are analyzed by a processor 914 that is similar to the processordescribed above, and which is coupled to a memory 916 that storesinformation related to wireless data processing. Processor 914 isfurther coupled to a FLO channel 918 component that facilitatesprocessing FLO information associated with one or more respective userdevices 904.

A modulator 922 can multiplex a signal for transmission by a transmitter924 through transmit antenna 908 to user devices 904. FLO channelcomponent 918 can append information to a signal related to an updateddata stream for a given transmission stream for communication with auser device 904, which can be transmitted to user device 504 to providean indication that a new optimum channel has been identified andacknowledged.

What has been described above includes exemplary embodiments. It is, ofcourse, not possible to describe every conceivable combination ofcomponents or methodologies for purposes of describing the embodiments,but one of ordinary skill in the art may recognize that many furthercombinations and permutations are possible. Accordingly, theseembodiments are intended to embrace all such alterations, modificationsand variations that fall within the spirit and scope of the appendedclaims. Furthermore, to the extent that the term “includes” is used ineither the detailed description or the claims, such term is intended tobe inclusive in a manner similar to the term “comprising” as“comprising” is interpreted when employed as a transitional word in aclaim.

1. A method to process forward link only (FLO) wireless signals on acommunications device, comprising: receiving a FLO signal; processing aTime-Division Multiplexing (TDM) pilot comprising a TDM Pilot 1, a TDMPilot 2, a Wide-area Identification Channel (WIC), a Local-areaIdentification Channel (LIC), a Transition Pilot Channel, and aPositioning Pilot, from the FLO signal; processing an overheadinformation symbol (OIS) comprising a wide-area OIS and a local-areaOIS, from the FLO signal, wherein the wide-area OIS conveys informationrequired to locate relevant data symbols in a wide-area data channel;processing a Frequency-Division Multiplexing (FDM) pilot comprising awide-area FDM pilot and a local-area FDM pilot, from the FLO signal; andprocessing data comprising wide-area data and local-area data, from theFLO signal.
 2. The method of claim 1, wherein the TDM pilot, the OIS,the FDM pilot, and the data are organized into a superframe in the FLOsignal.
 3. The method of claim 2, wherein the superframe comprisesapproximately 1200 Orthogonal Frequency Division Multiplexing (OFDM)symbols.
 4. The method of claim 3, wherein each symbol comprises seveninterlaces of active sub-carriers.
 5. The method of claim 2, whereinapproximately 6 MHz of bandwidth is allocated to the FLO signal.
 6. Themethod of claim 5, wherein the superframe comprises approximately 200OFDM symbols per allocated MHz.
 7. The method of claim 2, wherein theTransition Pilot Channel comprises a Wide-area Transition Pilot Channel(WTPC) and a Local-area Transition Pilot Channel (LTPC).
 8. The methodof claim 7, wherein the superframe comprises a plurality of OFDM symbolsidentifiable by consecutively numbered indeces, wherein an OFDM symbolfor the WTPC occurs at least at indices having a value V represented bythe expressionV=19+W+F×i, wherein W comprises a total number of OFDM symbols in thesuperframe associated with the wide-area data, wherein F comprises atotal number of OFDM symbols in the superframe, and wherein i isselected from the numbers zero (0), one (1), two (2) and three (3). 9.The method of claim 7, wherein the superframe comprises a plurality ofOFDM symbols identifiable by consecutively numbered indeces, wherein anOFDM symbol for the WTPC occurs at least at indices having a value Vrepresented by the expressionV=18+F×i, wherein F comprises a total number of OFDM symbols in thesuperframe, and wherein i is selected from the numbers one (1), two (2)and three (3).
 10. The method of claim 7, wherein the superframecomprises a plurality of OFDM symbols identifiable by consecutivelynumbered indeces, wherein an OFDM symbol for the LTPC occurs at least atindices having a value V represented by the expressionV=20+W+F×i, wherein W comprises a total number of OFDM symbols in thesuperframe associated with the wide-area data, wherein F comprises atotal number of OFDM symbols in the superframe, and wherein i isselected from the numbers zero (0), one (1), two (2) and three (3). 11.The method of claim 7, wherein the superframe comprises a plurality ofOFDM symbols identifiable by consecutively numbered indeces, wherein anOFDM symbol for the WTPC occurs at least at indices having a value Vrepresented by the expressionV=18+F×i, wherein F comprises a total number of OFDM symbols in thesuperframe, and wherein i is selected from the numbers one (1), two (2)and three (3).
 12. The method of claim 1, wherein the TDM Pilot 1, TDMPilot 2, WIC, and LIC occur consecutively in the FLO signal.
 13. Themethod of claim 1, wherein the FDM Pilot is frequency divisionmultiplexed with the OIS in the FLO signal.
 14. The method of claim 1,wherein the Transition Pilot Channel is time division multiplexed withthe OIS and the data in the FLO signal.
 15. The method of claim 1,wherein the Transition Pilot Channel comprises a Wide-area TransitionPilot Channel (WTPC) and a Local-area Transition Pilot Channel (LTPC).16. The method of claim 1, wherein receiving the FLO signal compriseswireless receiving the FLO signal.
 17. An apparatus, comprising: areceiver configured to receive a forward link only (FLO) signal; a FLOchannel component configured to process a Time-Division Multiplexing(TDM) pilot, an overhead information symbol (OIS), and aFrequency-Division Multiplexing (FDM) pilot from the FLO signal; and aprocessor configured to analyze data comprising wide-area data andlocal-area data processed from the FLO signal, wherein the TDM pilotcomprises a TDM Pilot 1, a TDM Pilot 2, a Wide-area IdentificationChannel (WIC), a Local-area Identification Channel (LIC), a TransitionPilot Channel, and a Positioning Pilot, wherein the OIS comprises awide-area OIS and a local-area OIS, the wide-area OIS conveyinginformation required to locate relevant data symbols in a wide-area datachannel, and wherein the FDM pilot comprises a wide-area FDM pilot and alocal-area FDM pilot.
 18. The apparatus of claim 17, wherein the TDMpilot, the OIS, the FDM pilot, and the data are organized into asuperframe in the FLO signal.
 19. The apparatus of claim 18, wherein thesuperframe comprises approximately 1200 Orthogonal Frequency DivisionMultiplexing (OFDM) symbols.
 20. The apparatus of claim 19, wherein eachsymbol comprises seven interlaces of active sub-carriers.
 21. Theapparatus of claim 18, wherein approximately 6 MHz of bandwidth isallocated to the FLO signal.
 22. The apparatus of claim 21, wherein thesuperframe comprises approximately 200 OFDM symbols per allocated MHz.23. The apparatus of claim 18, wherein the Transition Pilot Channelcomprises a Wide-area Transition Pilot Channel (WTPC) and a Local-areaTransition Pilot Channel (LTPC).
 24. The apparatus of claim 23, whereinthe superframe comprises a plurality of OFDM symbols identifiable byconsecutively numbered indeces, wherein an OFDM symbol for the WTPCoccurs at least at indices having a value V represented by theexpressionV=19+W+F×i, wherein W comprises a total number of OFDM symbols in thesuperframe associated with the wide-area data, wherein F comprises atotal number of OFDM symbols in the superframe, and wherein i isselected from the numbers zero (0), one (1), two (2) and three (3). 25.The apparatus of claim 23, wherein the superframe comprises a pluralityof OFDM symbols identifiable by consecutively numbered indeces, whereinan OFDM symbol for the WTPC occurs at least at indices having a value Vrepresented by the expressionV=18+F×i, wherein F comprises a total number of OFDM symbols in thesuperframe, and wherein i is selected from the numbers one (1), two (2)and three (3).
 26. The apparatus of claim 23, wherein the superframecomprises a plurality of OFDM symbols identifiable by consecutivelynumbered indeces, wherein an OFDM symbol for the LTPC occurs at least atindices having a value V represented by the expressionV=20+W+F×i, wherein W comprises a total number of OFDM symbols in thesuperframe associated with the wide-area data, wherein F comprises atotal number of OFDM symbols in the superframe, and wherein i isselected from the numbers zero (0), one (1), two (2) and three (3). 27.The apparatus of claim 23, wherein the superframe comprises a pluralityof OFDM symbols identifiable by consecutively numbered indeces, whereinan OFDM symbol for the WTPC occurs at least at indices having a value Vrepresented by the expressionV=18+F×i, wherein F comprises a total number of OFDM symbols in thesuperframe, and wherein i is selected from the numbers one (1), two (2)and three (3).
 28. The apparatus of claim 17, wherein the TDM Pilot 1,TDM Pilot 2, WIC, and LIC occur consecutively in the FLO signal.
 29. Theapparatus of claim 17, wherein the FDM Pilot is frequency divisionmultiplexed with the OIS in the FLO signal.
 30. The apparatus of claim17, wherein the Transition Pilot Channel is time division multiplexedwith the OIS and the data in the FLO signal.
 31. The apparatus of claim17, wherein the Transition Pilot Channel comprises a Wide-areaTransition Pilot Channel (WTPC) and a Local-area Transition PilotChannel (LTPC).
 32. The apparatus of claim 17, wherein the receiver isconfigured to wirelessly receive the FLO signal.
 33. An apparatus forprocessing forward link only (FLO) wireless signals, comprising: meansfor receiving a FLO signal; means for processing a Time-DivisionMultiplexing (TDM) pilot comprising a TDM Pilot 1, a TDM Pilot 2, aWide-area Identification Channel (WIC), a Local-area IdentificationChannel (LIC), a Transition Pilot Channel, and a Positioning Pilot, fromthe FLO signal; means for processing an overhead information symbol(OIS) comprising a wide-area OIS and a local-area OIS, from the FLOsignal, wherein the wide-area OIS conveys information required to locaterelevant data symbols in a wide-area data channel; means for processinga Frequency-Division Multiplexing (FDM) pilot comprising a wide-area FDMpilot and a local-area FDM pilot, from the FLO signal; and means forprocessing data comprising wide-area data and local-area data, from theFLO signal.
 34. A computer readable storage medium encoded thereon withinstructions that when executed cause an apparatus to perform a methodof processing forward link only (FLO) wireless signals , said methodcomprising: receiving a FLO signal; processing a Time-DivisionMultiplexing (TDM) pilot comprising a TDM Pilot 1, a TDM Pilot 2, aWide-area Identification Channel (WIC), a Local-area IdentificationChannel (LIC), a Transition Pilot Channel, and a Positioning Pilot, fromthe FLO signal; processing an overhead information symbol (OIS)comprising a wide-area OIS and a local-area OIS, from the FLO signal,wherein the wide-area OIS conveys information required to locaterelevant data symbols in a wide-area data channel; processing aFrequency-Division Multiplexing (FDM) pilot comprising a wide-area FDMpilot and a local-area FDM pilot, from the FLO signal; and processingdata comprising wide-area data and local-area data, from the FLO signal.35. A method to transmit forward link only (FLO) wireless signals from atransmission device, comprising: processing data comprising wide-areadata and local-area data; appending a Frequency-Division Multiplexing(FDM) pilot comprising a wide-area FDM pilot and a local-area FDM pilot,to the data; appending an overhead information symbol (OIS) comprising awide-area OIS and a local-area OIS, to the data, wherein the wide-areaOIS conveys information required to locate relevant data symbols in awide-area data channel; appending a Time-Division Multiplexing (TDM)pilot comprising a TDM Pilot 1, a TDM Pilot 2, a Wide-areaIdentification Channel (WIC), a Local-area Identification Channel (LIC),a Transition Pilot Channel, and a Positioning Pilot, to the data;modulating the data and appended pilots and symbols for transmission asa FLO signal; and transmitting the FLO signal.
 36. The method of claim35, wherein transmitting the wide-area data, FDM pilot, OIS, andIdentification Channel comprises radiating identical waveforms from agroup of transmitters with a footprint covering one or more metropolitanareas.
 37. The method of claim 36, wherein transmitting the local-areadata, FDM pilot, OIS, and Identification Channel comprises radiatingidentical waveforms from a group of transmitters with a footprint thatis smaller in area than the footprint of the group of transmitterstransmitting the wide-area data, FDM pilot, OIS, and IdentificationChannel.
 38. An apparatus, comprising: a processor configured to processdata comprising wide-area data and local-area data; a forward link only(FLO) channel component configured to append a Frequency-DivisionMultiplexing (FDM) pilot comprising a wide-area FDM pilot and alocal-area FDM pilot; an overhead information symbol (OIS) comprising awide-area OIS and a local-area OIS; and a Time-Division Multiplexing(TDM) pilot comprising a TDM Pilot 1, a TDM Pilot 2, a Wide-areaIdentification Channel (WIC), a Local-area Identification Channel (LIC),a Transition Pilot Channel, and a Positioning Pilot, to the data; amodulator configured to modulate the data and appended pilots andsymbols for transmission as a FLO signal; and a transmitter configuredto transmit the FLO signal, wherein the wide-area OIS conveysinformation required to locate relevant data symbols in a wide-area datachannel.
 39. The apparatus of claim 38, comprising a first group oftransmitters configured to transmit the wide-area data, FDM pilot, OIS,and Identification Channel by radiating identical waveforms and with afootprint covering one or more metropolitan areas.
 40. The apparatus ofclaim 39, comprising a second group of transmitters configured totransmit the local-area data, FDM pilot, OIS, and Identification Channelby radiating identical waveforms and with a footprint that is smaller inarea than the footprint of the first group of transmitters.